Distribution of human papillomavirus genotypes in invasive cervical cancer in Italy: a representative, single institution case series.

Despite worldwide human papillomavirus (HPV) types distribution showed constant rates of HPV 16/18 in cervical cancers, regional variations have been consistently documented. Very little data is available on HPV genotype prevalence among Italian women with invasive cervical cancer. This study aims to determine the HPV type distribution in cervical specimens obtained from Italian women diagnosed with invasive cervical cancer and referred to the European Institute of Oncology (IEO). Two hundred-sixty eight cervical specimens were obtained from patients diagnosed with invasive cervical cancer referred to the European Institute of Oncology between 1996 and 2006. Following preparation, all cervical samples were sent to laboratories at the International Agency for Research on Cancer (IARC, Lyon, France) for DNA extraction and HPV typing by the multiplex PCR/APEX assay. The study population was divided into four groups from different macro regions: (i) Milan and surrounding area (n=57, 21.3%), (ii) northern Italy (n=81, 30.2%), (iii) central Italy (n=64, 23.9%) and (iv) southern Italy (n=66, 24.6%). The present study is the first at our knowledge that examines a fair number of Italian cervical cancers, about one tenth of all estimated cervical cancer cases occurring yearly, distributed across the whole country. Two-hundred and fifty-one patients (93.7%) resulted HPV DNA positive; of these 201 patients (80.1%) presented a single infection, whereas 50 women (19.9%) presented multiple infection. One hundred and eighty-nine specimens (75.3%) tested positive for either HPV 16 or HPV 18, whereas 62 (24.7%) resulted positive for other high-risk HPV genotypes only. The proportion of HPV 16/18 positive invasive cervical cancers was similar for all the four geographical Italian areas considered. A statistically significant association with younger age and earlier stage was observed for HPV 16/18 related invasive cervical cancers. The results demonstrate that the proportion of HPV 16/18 cervical cancers is fairly constant in all the areas and covers more than 70% of Italian cervical cancer cases. This observation strengthens the decision to start the vaccination programme in all the Italian regions. In addition, the present study provides new and original data on the genotype related differences of the disease that are worth of further investigation.